Table 2.

Response to Neoadjuvant Chemotherapy by Clinical Stage at Diagnosis among NCDB Breast Cancer Cohort – All tumor subtypes (n=33,162)

			Pathological Stage after Neoadjuvant Chemotherapy												Total
			ypT0			ypT1			ypT2			ypT3
			ypN0	ypN1mic	ypN1	ypN0	ypN1mic	ypN1	ypN0	ypN1mic	ypN1	ypN0	ypN1mic	ypN1
Clinical Stage at Diagnosis	cT1	cN0	812	9	23	3,017	156	562	330	42	200	28	2	46	5,227
			15.5%	0.2%	0.4%	57.7%	3.0%	10.8%	6.3%	0.8%	3.8%	0.5%	0.0%	0.9%
		cN1	561	30	139	413	96	1,088	45	7	153	6	2	27	2,567
			22.0%	1.2%	5.4%	16.1%	3.7%	42.4%	1.8%	0.3%	6.0%	0.2%	0.1%	1.1%
	cT2	cN0	2,026	20	41	3,470	172	449	2,644	175	776	168	15	93	10,049
			20.2%	0.2%	0.4%	34.5%	1.7%	4.5%	26.3%	1.7%	7.7%	1.7%	0.2%	0.9%
		cN1	1,856	50	258	1,519	224	1,784	544	127	1,900	43	9	188	8,502
			21.8%	0.6%	3.0%	17.9%	2.6%	21.0%	6.4%	1.5%	22.4%	0.5%	0.1%	2.2%
	cT3	cN0	446	5	10	710	42	122	535	58	192	437	32	219	2,808
			15.9%	0.2%	0.4%	25.3%	1.5%	4.3%	19.1%	2.1%	6.8%	15.6%	1.1%	7.8%
		cN1	669	31	97	718	121	590	311	57	650	176	34	555	4,009
			16.7%	0.8%	2.4%	17.9%	3.0%	14.7%	7.8%	1.4%	16.2%	4.4%	0.9%	13.8%
	Total		6,370 19.2%	145 0.4%	568 1.7%	9,847 29.7%	811 2.4%	4,595 13.9%	4,409 13.3%	466 1.4%	3,871 13.3%	858 3.0%	94 0.3%	1,128 3.4%	33,162

Green – Breast + axilla pCR

Pink – Breast-only pCR

Blue - Node-only pCR

Yellow – No stage change

Orange – Upstage

Gray – EXCLUDED from main analysis: Discordant (i.e., breast underwent upstage while axilla was downstaged or vice versa) or Downstage without pCR